GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / ide / ide-park.c
1 #include <linux/kernel.h>
2 #include <linux/gfp.h>
3 #include <linux/ide.h>
4 #include <linux/jiffies.h>
5 #include <linux/blkdev.h>
6
7 DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
8
9 static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
10 {
11         ide_hwif_t *hwif = drive->hwif;
12         struct request_queue *q = drive->queue;
13         struct request *rq;
14         int rc;
15
16         timeout += jiffies;
17         spin_lock_irq(&hwif->lock);
18         if (drive->dev_flags & IDE_DFLAG_PARKED) {
19                 int reset_timer = time_before(timeout, drive->sleep);
20                 int start_queue = 0;
21
22                 drive->sleep = timeout;
23                 wake_up_all(&ide_park_wq);
24                 if (reset_timer && del_timer(&hwif->timer))
25                         start_queue = 1;
26                 spin_unlock_irq(&hwif->lock);
27
28                 if (start_queue)
29                         blk_run_queue(q);
30                 return;
31         }
32         spin_unlock_irq(&hwif->lock);
33
34         rq = blk_get_request(q, READ, __GFP_RECLAIM);
35         rq->cmd[0] = REQ_PARK_HEADS;
36         rq->cmd_len = 1;
37         rq->cmd_type = REQ_TYPE_DRV_PRIV;
38         rq->special = &timeout;
39         rc = blk_execute_rq(q, NULL, rq, 1);
40         blk_put_request(rq);
41         if (rc)
42                 goto out;
43
44         /*
45          * Make sure that *some* command is sent to the drive after the
46          * timeout has expired, so power management will be reenabled.
47          */
48         rq = blk_get_request(q, READ, GFP_NOWAIT);
49         if (IS_ERR(rq))
50                 goto out;
51
52         rq->cmd[0] = REQ_UNPARK_HEADS;
53         rq->cmd_len = 1;
54         rq->cmd_type = REQ_TYPE_DRV_PRIV;
55         elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
56
57 out:
58         return;
59 }
60
61 ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
62 {
63         struct ide_cmd cmd;
64         struct ide_taskfile *tf = &cmd.tf;
65
66         memset(&cmd, 0, sizeof(cmd));
67         if (rq->cmd[0] == REQ_PARK_HEADS) {
68                 drive->sleep = *(unsigned long *)rq->special;
69                 drive->dev_flags |= IDE_DFLAG_SLEEPING;
70                 tf->command = ATA_CMD_IDLEIMMEDIATE;
71                 tf->feature = 0x44;
72                 tf->lbal = 0x4c;
73                 tf->lbam = 0x4e;
74                 tf->lbah = 0x55;
75                 cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
76                 cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
77         } else          /* cmd == REQ_UNPARK_HEADS */
78                 tf->command = ATA_CMD_CHK_POWER;
79
80         cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
81         cmd.protocol = ATA_PROT_NODATA;
82
83         cmd.rq = rq;
84
85         return do_rw_taskfile(drive, &cmd);
86 }
87
88 ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
89                       char *buf)
90 {
91         ide_drive_t *drive = to_ide_device(dev);
92         ide_hwif_t *hwif = drive->hwif;
93         unsigned long now;
94         unsigned int msecs;
95
96         if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
97                 return -EOPNOTSUPP;
98
99         spin_lock_irq(&hwif->lock);
100         now = jiffies;
101         if (drive->dev_flags & IDE_DFLAG_PARKED &&
102             time_after(drive->sleep, now))
103                 msecs = jiffies_to_msecs(drive->sleep - now);
104         else
105                 msecs = 0;
106         spin_unlock_irq(&hwif->lock);
107
108         return snprintf(buf, 20, "%u\n", msecs);
109 }
110
111 ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
112                        const char *buf, size_t len)
113 {
114 #define MAX_PARK_TIMEOUT 30000
115         ide_drive_t *drive = to_ide_device(dev);
116         long int input;
117         int rc;
118
119         rc = kstrtol(buf, 10, &input);
120         if (rc)
121                 return rc;
122         if (input < -2)
123                 return -EINVAL;
124         if (input > MAX_PARK_TIMEOUT) {
125                 input = MAX_PARK_TIMEOUT;
126                 rc = -EOVERFLOW;
127         }
128
129         mutex_lock(&ide_setting_mtx);
130         if (input >= 0) {
131                 if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
132                         rc = -EOPNOTSUPP;
133                 else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
134                         issue_park_cmd(drive, msecs_to_jiffies(input));
135         } else {
136                 if (drive->media == ide_disk)
137                         switch (input) {
138                         case -1:
139                                 drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
140                                 break;
141                         case -2:
142                                 drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
143                                 break;
144                         }
145                 else
146                         rc = -EOPNOTSUPP;
147         }
148         mutex_unlock(&ide_setting_mtx);
149
150         return rc ? rc : len;
151 }